Gustav ibeuggee



UNITED STATES PATENT EEICE.

GUSTAV IBRGGER, OF NORDEN, OSTFRIESSLAND, PRUSSIA, GERMANY.

cUPoLA-FURNACE.

SPECIFICATION forming part of Letters Patent No. 240,135, dated April 12, 1881.

Application tiled April 20, 1880.

September 12, 1879, and in Germany September 9, 1879.

To all whom it may concern:

Be it known that I, GUs'rAv IBRGGER, of the city of Norden, Ostfriessland, in the Kin gdom ofPrussia, German Empire, have invented Improvements in Cupola-Furnaces and in the Methods of Melting \Vroiight and Pig Iron in said Cupola-Furnaces, of which the following is a specification.

This invention relates to improvements in the construction of cupola-furnaces and in a method of melting wrought and pig iron therein in any desired proportions, so that the resultin g product is equal to malleable iron and nearly equal to steel.

The invention consists of a furnace with a central bottom openin g and a collecting trough or well below the furnace, the well being provided with a dischargeopening, a slag-opening, and a supply-opening above the dischargeopening, together with a blast-tube for' supplying the required quantity of hot air to the combustible lire-gases which have passed from the furnace into the well.

The cupola-furnaces heretofore in use were provided with a collecting-hearth which had to be heated up by a separate lire. This firing up is dispensed with by the use of a collecting-well below the furnace, as the lire-gases, which issue through the bottom opening into the well, heat up the same without preparatory firing. Another advantage of the collectin g-well, as compared to other constructions of cupola-furnaces, consists in the fact that the iron is not only kept from the beginning to the end of the melting process in ahot and liquid state, but gets even hotter toward the end of the same, while in the construction of cupola-furnaces heretofore in use the heat of the melting iron is reduced. The bottom well admits also of the tuyeres being arranged in a lower position in the furnace, so as to necessitate less coke in charging.

In the accompanying drawings, Figure 1 represents a front elevation of my improved cupola-furnace; and Figs. 2 and 3 are, respectivcly, a vertical longitudinal and horizontal section of the same on lines ma* and y y, Fig. l.

Similar letters of reference indicate corresponding parts.

In the drawings, A represents a cupola-furnace of any improved forni and construction, the shaft of which has any desired cross-section. For the purpose of melting larger bars of iron the elongated section shown in Fig. 3 is to be preferred. This shape also facilitates the more uniform distribution of the blast in the furnace. The furnace is providedat both front and rear with two groups or series of vertical blast-openings, a a, the openings of one series alternating with that ofthe other series, one series being also placed somewhat higher in the walls than the other. The vertical openings have anarrow oblong form, and diminish in height 01 taper toward the outer surface of the walls. These vertical openings a have the advantage that the slag cannot close them, and that the slag cannot so easily be chilled by the blast.

Below the furnace A is larranged a collecting trough or well, B, the bottom of which is slightly inclined toward the discharge-openin g b, through which the melted metal is drawn off. The opposite end wall of the Well B has an opening, d, above the level of the opening b for drawing off the slag. The rear wall can also be entirely removed when the collecting trough or well has 'to be repaired. The well B is covered by an arched-top wall and connected with the furnace A by a small central opening, e, of any desired cross-section. Somewhat above the lowest point of the furnace is arranged a discharge-opening, f. The collecting-well B has at its upper front part, above the opening b, an opening, g, which may be closed by a sliding door. Through this opening the well is charged with wrou gh t-iron scrap and charcoal, it serving also for observing the molten metal and stirring it up from time to time. A small blast-tube, h, opens into the well and is connected with one of the main trunks D D of the air-blast.

lf it is desired to simply melt the pig-iron, the bottom of the furnace is covered with kindling-wood, and a layer of a coke placed upon the same and charged with pig-iron, 86e., as customaryin cupola-furnaces. The fire is then lighted and the blast put on through the tuyeres, which open into the encircling sheet-metal (No model.) Patented in France September 13, 1879, in Belgium September 22, 1879, in England jacket of the furnace, the fire-gases passing through the bottom opening, e, into the well B, and heating up the same preparatory to receiving the melted iron, so that it is not chilled when running in, which is a great advantage as compared with the cupola-furnace without such Wells, in which the liquid iron has to do the heating of the hearth itself. The unconsumed fire-gases from the furnace are burned in the well by the blast supplied by the tube h.

When it is desired to melt and unite pigiron with wrought-iron, such as scraps, brokenup pieces, 85e., the latter is placed rst in the trough or well B, and a small quantity of charcoaladded thereto. Thefurnace is then charged and fired, as before described. The blast is then turned on andthe top of the furnace covered, so that the gases have to pass through the bottom opening into the well, where the57 are burned, so as to produce an intense heat therein, which melts the wrought-iron. This is continued until all the wrought-iron is thoroughly melted and collected at the bottom of the well. The furnace is next charged with coke and pig-iron, which latter, on melting, passes gradually with the gases of combustion into the trough or well and unites itself with the Wrought-iron at a high temperature, so that an intimate union is obtained. When all the pig-iron is melted and united with the wroughtiron the molten metal is thoroughly stirred and then drawn olf. If the same process has to be repeated, the slag is removed and a new i sired to be melted. The Well, however, may be y made smaller by moving the rear Wall nearer up to the bottoni opening, e. The well can also be made movable, which has the advantage that it can be charged again after the melted metal and slag have been drawnoif, it being then moved back into place below the furnace.

Having thus described myinvention, I claimv as new and desire to secure by Letters Patent- In acupola-furnace, the combination ot' a furnace, A, having a central bottom opening, c, with a collecting trough or well, B, arranged below the saine, and provided with a dischargeopening, b, a slag-opening, d, a supply-opening, g, above the discharge-opening, and a blast-tube, h, substantially as specified.

ln testimony whereofl have signed my name to this specification in the presence of two subscribing witnesses.

GUS'PAV IBRGGER.

Witnesses z THEoDoR HELLWIG, CARL FEHLERT. 

